Curated OER
Interior and Exterior Angles of Polygons
For this angles of polygons worksheet, 10th graders solve and complete 18 different problems that include determining various interior and exterior angles. First, they determine the measure of various angles described in the first half...
Curated OER
Triangle Fundamentals
In this geometry worksheet, students observe a triangle marked with three angles and are given two measures to find the missing third measure. A second diagram is given with six angles. There are 20 questions.
Curated OER
Geometry of Triangles Using a Protractor
Seventh graders use a protractor to measure angles and solve a problem involving distance. For this measuring angles with a protractor lesson plan, 7th graders calculate the distance of a line on a diagram by using a protractor to...
Curated OER
Tricky Triangle
In this triangle instructional activity, high schoolers solve 1 word problem about the lengths of a triangle. Students determine the length of the longest side given the ratio of the angle measures.
Curated OER
Angles And Triangles
Seventh graders participate in a activity that is focused upon the concepts of classifying different angles and triangles. They practice classifying triangles according to its kind that includes types of angles, congruence, and vertices....
Curated OER
Sum of Angles
In this sum of angles activity, 6th graders solve and complete 6 different types of problems. First, they identify different alternate and corresponding angles. Then, students state what the angles of a triangle add up to and how they...
Curated OER
Inscribed Angles
Students calculate the inscribed angle of a triangle. In this geometry lesson, students identify the angle created by intersection of a triangle and a circle. They see the relationship between the arc and the angle.
Improving Measurement and Geometry in Elementary Schools
The Sum of the Interior Angles of a Polygon
Junior geometers discover that polygons can be decomposed into triangles and that the number of triangles can be determined by a rule. Note that the Geometer’s Sketchpad® software is required to carry out all components of this...
Curated OER
A Special Relationship
Students discover the relationships of the lengths of the sides of right triangles and right triangles using a series of drawings on dot paper. They investigate and solve problems of standard (customary and metric units) and non-standard...
Curated OER
Isosceles Triangle Theorem
In this geometry worksheet, students differentiate between regular triangles and isosceles triangles. They apply the converse theorem and the vertex angle. There are eleven questions with an answer key.
Curated OER
Identifying Angles
Students identify names of angles. They use a large clock to demonstrate angles using certain times of day. Given a geoboard, students create figures with acute, right, and obtuse angles.
Curated OER
Art or Junk? Discovering the Triangle Inequality
Middle schoolers study the triangle inequality. They will identify, compare, and analyze attributes of two and three-dimensional shapes. Then they develop vocabulary to describe the attributes. They also use manipulatives to analyze the...
Curated OER
Special Segments is a Triangle
In this geometry worksheet, 10th graders examine the special segments that occur in a triangle. The three page worksheet contains twenty-five problems. Answers are not included.
Curated OER
Trig Cheat Sheet
Your pre-calculus learners will make use of this wonderful cheat sheet that summarizes all things trigonometric. Definitions based on both the unit circle and the right triangle are included, as well as many convenient trigonometric...
Curated OER
Drawing a Triangle with Cabri Junior
Learners draw triangles on their graphing calculators using the Cabri Junior application. In this graphing calculator lesson, students follow step by step directions to create triangles on their calculator. They identify the type of...
Curated OER
Angles
In this math learning exercise, students measure a series of angles. Then they measure the angles in the triangles and determine the sum of the angles.
Curated OER
Triangle worksheets
In this geometry worksheet, 10th graders explore triangle properties, including the sum of the measures of the angles of a triangle, the triangle inequalities, properties of isosceles triangles, properties of congruent triangles, and...
Curated OER
Similar Triangles
Students differentiate between similar and congruent triangles. For this geometry lesson, students identify the missing side and angle of a triangle. They identify the different ratio and proportion of the sides of a triangle.
Curated OER
The Greedy Triangle-Intro to Geometric Shapes
In this geometry lesson, learners read The Greedy Triangle and use geoboards to construct geometric shapes. They identify the number of sides and angles each shape has.
Willow Tree
Interior Angles, Exterior Angles, and Diagonals of Polygons
How does the number of sides of a polygon affect the angle measures? Learners recognize a pattern in finding the total measure of interior and exterior angles and the number of diagonals. They use the patterns to calculate...
EngageNY
Correspondence and Transformations
Looking for a strategy to organize the information related to transformations? The materials ask pupils to identify a sequence of rigid transformations, identify corresponding angles and sides, and write a congruence statement. They...
Inside Mathematics
Rhombuses
Just what does it take to show two rhombuses are similar? The assessment task asks pupils to develop an argument to show that given quadrilaterals are rhombuses. Class members also use their knowledge of similar triangles to show two...
Willow Tree
The Pythagorean Theorem
There isn't a more popular geometry formula than the Pythagorean Theorem! Learners understand the special side relationships in a right triangle. They use the Pythagorean Theorem to find missing sides and to solve problems. They begin...
EngageNY
Using Trigonometry to Determine Area
What do you do when you don't think you have enough information? You look for another way to do the problem! Pupils combine what they know about finding the area of a triangle and trigonometry to determine triangle area when they don't...